Modern electronic systems, such as computers, contain clock generation circuits that generate one or more frequencies at which electronic components in the system operate. Electronic systems are tested to guarantee system reliability at a given operating frequency. One typical reliability test is called wear-out acceleration. As is known in the art, wear-out acceleration is used to accelerate the aging of electronic systems in order to determine possible mechanisms that cause failure or reduced reliability as electronic systems age. Wear-out acceleration operates components beyond their specified operating range, for instance, at one and a half times their nominal voltage and at elevated temperatures for a specified time period, typically hours or days instead of years.
Information from wear-out acceleration is used to adjust such things as frequency of operation of the electronic system. A low frequency is chosen based on the wear-out acceleration information so that the electronic system will operate correctly when the system has been aged. Frequency of operation of an electronic system therefore has a “guard band” used to ensure proper operation over the life of the electronic system.
There is a need to provide techniques for modifying the frequency of electronic systems as the systems age to minimize the guard band and operate a system at near peak performance over its entire lifetime.